#include <iostream>
using namespace std;

int main()
{
    //std::cout<<"hello world\n";
    double a = 10.5;
    int b = 10;
    const char *s = "hello";
    //std::endl:输出一个回车到终端  清空缓冲区
    std::cout<<a<<" "<<b<<" "<<s<<std::endl;
    std::cin>>a;
    std::cout<<"a = "<<a<<"sizeof(a)"<<sizeof(a)<<std::endl;          
    return 0;
}